REFERENCE / WORDS THAT CHANGE INTERPRETATION
Acquisition. Becoming infected; different from encountering a person with an infection.
Asymptomatic. No recognized symptoms. This does not by itself establish absence of disease or infectiousness.
Colonization. An organism is present without established disease attributable to it.
Confidence interval. A statistical uncertainty interval within a study's assumptions and sampling frame.
Current infection. Infection present now, as opposed to a historical antibody or a successfully treated infection.
Incidence. New infections over a defined interval; not the same as prevalence.
NAAT / PCR. A nucleic acid amplification test; PCR is one type. Detection is specific to the organism and specimen.
Per-act probability. A transmission estimate for one defined contact, conditional on relevant source infection and other assumptions.
PEP / PrEP. Postexposure / preexposure prophylaxis. The medicine, indication and timing depend on the infection.
Prevalence. The proportion with a defined infection or test finding in a specified population and period.
Resistance. Reduced susceptibility of an organism to a medicine; not the same as the person being resistant.
Serology. Testing blood for antibodies or antigens. Its meaning depends on the marker and infection.
Shedding. Release of an organism from infected tissue; may occur without visible symptoms.
Test of cure / retest. A test of cure checks eradication after treatment; a later retest often checks for reinfection.
U=U. Undetectable equals untransmittable: sustained HIV viral suppression prevents sexual transmission.
Window period. The time after acquisition before a particular test can reliably detect the infection.
Clinical terminology and interpretation follow the infection-specific guidance cited in the main sections. The mathematical definitions are stated explicitly in Appendices A-C.